US7049865B2

Power-on detect circuit for use with multiple voltage domains

Summary by NHIP

Multi-domain power-on detection circuit

The circuit monitors proxy signals from multiple voltage domains to generate control signals indicating when specific voltage sources reach threshold levels. A comparator creates a difference signal between proxy levels, which an inverter converts into a control output, while additional logic gates combine signals from separate analyzers to manage cross-domain conditions.

Claim Score by NHIP

Read claim 24, the broadest

Abstract

Embodiments of the present invention include a circuit, a method, and a system for power-on detect circuitry for use with multiple voltage domains.

US7049865B2, drawing sheet 1
Sheet 1 of 6

Term

Term ended

Expired 5 March 2024, 2.6 years ago.

  1. Priority and filed
  2. Granted
  3. Expired
  4. Today

33 claims: 4 independent, 29 dependent

  1. 1
    A circuit comprising:a first terminal adapted to manifest a first proxy signal that reflects a first level of a first voltage source of a first voltage domain;a second terminal adapted to manifest a second proxy signal at a second level of a second voltage source of a second voltage domain;and a first analyzer, coupled to the first and second terminals, adapted to receive the first and second proxy signals and to generate, in response, a first control signal indicative for said first voltage domain, whether the second voltage source has reached a first threshold level in said second voltage domain.
  2. 18
    An integrated circuit comprising:a first operational circuit, coupled to a first voltage source, adapted to receive a first voltage from the first voltage source, defining a first voltage domain;a second operational circuit, coupled to a second voltage source, adapted to receive a second voltage from the second voltage source, defining a second voltage domain;and a power-on detect circuit, coupled to the first and second voltage sources, adapted to output a first control signal for the first voltage domain indicating whether the second voltage has reached a first threshold level in the second voltage domain.
  3. 24
    Broadest claimClaim Score 65, broad(NHIP)A method comprising:receiving a first control signal from a power-on detect circuit coupled to receive a first and second voltage from a first and second voltage source which respectively define a first and second voltage domain, said first control signal indicating, for the first voltage domain, that the second voltage has reached a first threshold level in the second voltage domain;receiving a first logic signal from an operational circuit of the second voltage domain;qualifying the first logic signal with the first control signal;and transmitting a second logic signal to an operational circuit of the first voltage domain.
  4. 30
    A system comprising:an integrated circuit including;a first operational circuit, coupled to a first voltage source, adapted to receive a first voltage from the first voltage source, defining a first voltage domain;a second operational circuit, coupled to a second voltage source, adapted to receive a second voltage from the second voltage source, defining a second voltage domain;and a power-on detect circuit, coupled to the first and second voltage sources, adapted to output a first control signal for the first voltage domain indicating whether the second voltage has reached a first threshold level In the second voltage domain;and a dynamic random access memory coupled to the second operational circuit of the integrated circuit;and an input/output interface coupled to the second operational circuit of the integrated circuit.